Diodes Incorporated ZSM560GTA

Overview

ZSM560GTA from Zetex Semiconductors is a three-terminal under-voltage monitor IC designed for power-on reset and brownout detection in 5 V microprocessor systems. It features a precise 4.6 V threshold with 20 mV hysteresis, open-collector output sinking ≥10 mA, guaranteed operation from 1.0 V to 6.5 V supply, and internal clamp diode for RC delay network discharge.

For engineers reviewing the ZSM560GTA datasheet, ZSM560GTA pinout, ZSM560GTA application, or ZSM560GTA equivalent, key selection criteria include threshold accuracy across −40°C to +85°C, sink current capability at low V_CC, propagation delay (1.5 µs), quiescent current (200 µA max), and TO-92/SOT-223 package compatibility with through-hole or surface-mount board layouts.

Technical Context

The ZSM560GTA integrates a precision bandgap voltage reference, comparator with built-in hysteresis, and open-collector NPN output stage. Its threshold is trimmed to 4.61 V (typ) with ±0.11 V variation over temperature and supply, and hysteresis of 20 mV prevents oscillation during slow-rising or noisy supply transitions.

Operation begins at V_CC = 1.0 V, holding output low until V_CC exceeds V_IH; if V_CC later falls below V_IL, output reasserts low. The internal clamp diode (V_F = 1.2 V @ 10 mA) enables controlled discharge of external timing capacitors in reset delay circuits.

Key Specifications

Pinout & Package

The ZSM560GTA is supplied in SOT-223 package (suffix G), with Pin 1 = V_CC, Pin 2 = GND, Pin 3 = Output (open-collector), Pin 4 = floating or internally connected to Pin 2 per datasheet.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar under-voltage monitor applications.

Compared with MAX691CPA+ and TL7705ACPSR, the ZSM560GTA offers integrated clamp diode and true open-collector output in compact SOT-223, making it optimal for cost-sensitive, space-constrained 5 V reset applications requiring RC-based delay tuning and multi-device reset bus sharing.

Availability

ZSM560GTA is available at Aetrix Electronics and suitable for microprocessor power-on reset, automotive body control modules, and battery-powered data loggers requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for ZSM560GTA includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Zetex Semiconductors (now part of Diodes Incorporated) specialized in high-performance analog and power management ICs, with emphasis on precision voltage references, supervisors, and discrete power devices.

The ZSM560 belongs to Zetex's voltage supervisor product line, engineered specifically for reliable, low-cost reset generation in 5 V embedded systems where accuracy, hysteresis stability, and minimal external components are critical.

FAQ

What is the minimum supply voltage required for ZSM560GTA to assert a valid reset?

The ZSM560GTA begins functional operation at V_CC = 1.0 V and holds its open-collector output low until V_CC exceeds the upper threshold (4.61 V typ). Below 1.0 V, behavior is undefined per absolute maximum ratings; thus, 1.0 V is the guaranteed lower limit for predictable reset assertion during power-up.

Can ZSM560GTA be used with a 3.3 V microcontroller reset input?

Yes - the open-collector output allows direct interface to 3.3 V logic by using a pull-up resistor to 3.3 V. The output saturation voltage is ≤0.4 V @ 2 mA sink, ensuring solid logic-low level. No level-shifter is needed, provided the MCU reset pin tolerates 5 V on its input when pulled high by external 5 V source.

How does the internal clamp diode function in a typical RC reset delay circuit?

In an RC delay network (resistor from V_CC to capacitor, capacitor to GND), the clamp diode conducts when V_CC drops, rapidly discharging the capacitor to ensure immediate reset reassertion. This eliminates reliance on slow natural RC decay, guaranteeing sub-microsecond response to brownout events.

Is ZSM560GTA pin-compatible with ZSM560C (TO-92 version)?

No - ZSM560C uses TO-92 with Pin 1 = Output, Pin 2 = GND, Pin 3 = V_CC, while ZSM560GTA (SOT-223) has Pin 1 = V_CC, Pin 2 = GND, Pin 3 = Output. Pin order differs; PCB layout and schematic symbol must be updated for package change despite identical electrical functionality.